package se.umu.cs.ldbn.client.utils;

import java.util.ArrayList;
import java.util.Collection;

import se.umu.cs.ldbn.client.core.Relation;
import se.umu.cs.ldbn.client.i18n.I18N;
import se.umu.cs.ldbn.client.io.LdbnParser;
import se.umu.cs.ldbn.client.io.LdbnParser.LDBN_TYPE;

import com.google.gwt.http.client.Response;
import com.google.gwt.user.client.DOM;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.Widget;

/**
 * Class with static methods for common function such as 
 * style properties to Widgets, checking the response of a server, regular
 * expression strings and others.
 * 
 * @author Nikolay Georgiev (ens07ngv@cs.umu.se)
 */
public final class Common {
	
	public final static int MIN_PASSWORD_LENGTH = 4; 
	/*
	 * regular expressions for validating user data, peace not if you change
	 * the expressions here you have to change them in the PHP scripts as well.
	 */
	public final static String NAME_REGEX = "([\\w]|\\-){1,20}";
	
	public final static String EMAIL_REGEX = "[a-z0-9._%+-]+@[a-z0-9.-]+\\.[a-z]{2,4}"; 
	
	/** 
	 * I should use Deferred Binding
	 * @see http://code.google.com/docreader/#p=google-web-toolkit-doc-1-5&s=google-web-toolkit-doc-1-5&t=DevGuideDeferredBindingReplacement  
	 **/
	public static native String getUserAgent() /*-{
		return navigator.userAgent.toLowerCase();
	}-*/;
	
	public static boolean isAgentIE() {
		return getUserAgent().contains("msie");
	}
	
	/**
	 * Set the transparent background colour of a widget
	 * 
	 * @param w Widget which will have a transparent background colour.
	 */
	public static void setBGTransparent(Widget w) {
		DOM.setStyleAttribute(w.getElement(), "background", "transparent");
	}
	
	/**
	 * Set a cursor of a widget to be a pointer, so when a mouse is over the 
	 * widget a pinter cursor is used. This is mainly used to indicate buttons.
	 * 
	 * @param w a Widget which will have a pinter as a cursor.
	 */
	public static void setCursorPointer(Widget w) {
		DOM.setStyleAttribute(w.getElement(), "cursor", "pointer");
	}
	
	public static Label createCursorLabel(String labelText) {
		Label l = new Label(labelText);
		setCursorPointer(l);
		return l;
	}
	
	public static HTML createCursorHTML(String html) {
		HTML l = new HTML(html);
		setCursorPointer(l);
		return l;
	}
	
	/**
	 * Check a response, returned by the server. The following checks are 
	 * being performed:
	 * If the status code return by the server is ok (200).
	 * If the returned xml is a valid LDBN xml.
	 * If the returned LDBN xml is with type message, if so the message is 
	 * displayed, unless the message has type = OK.
	 * Please note that u don't have to parse the response with the LdbnParser
	 * after calling this method. Just call LdbnParser.get() and the method you
	 * desire. 
	 * @param response a request response.
	 * @return true if no errors are returned by the server.
	 */
	public static boolean checkResponse(Response response) {
		if(response.getStatusCode() != 200) {
			Window.alert(I18N.messages().serverErrorCode(String.
					valueOf(response.getStatusCode())));
			return false;
		}
		String responce = response.getText();
		return checkResponceTextOnly(responce);
	}
	
	public static boolean checkResponceTextOnly(String responce) {
		System.out.println("-----------------------Server response-----------------------------");
		System.out.println(responce);
		System.out.println("---------------------End server response---------------------------");
		LdbnParser p = LdbnParser.get();
		LdbnParser.LDBN_TYPE type = p.parse(responce);
		if (type == LDBN_TYPE.unknown) {
			Window.alert(I18N.constants().serverErrorUnknownXML());
			return false;
		}
		if (type == LDBN_TYPE.msg && p.getMsgType() != LdbnParser.MSG_TYPE.ok) {
			Window.alert(p.getMsgText());
			return false;
		}
		
		return true;
	}
	
	public static Collection<Relation> deepCopyDecomposition(Collection<Relation> decomposition) {
		ArrayList<Relation> dc = new ArrayList<Relation>(decomposition.size());
		for (Relation r : decomposition) {
			if(r != null) {
				dc.add(r.clone());
			}
		}
		return dc;
	}
	
	public static String escapeHTMLCharacters(String str) {
		final StringBuilder result = new StringBuilder();
		char[] chars = new char[str.length()];
		str.getChars(0, str.length(), chars, 0);
		for (char character : chars) {
			if (character == '<') {
				result.append("&lt;");
			} else if (character == '>') {
				result.append("&gt;");
			} else if (character == '&') {
				result.append("&amp;");
			} else if (character == '\"') {
				result.append("&quot;");
			} else if (character == '\'') {
				result.append("&#039;");
			} else if (character == '(') {
				result.append("&#040;");
			} else if (character == ')') {
				result.append("&#041;");
			} else if (character == '#') {
				result.append("&#035;");
			} else if (character == '%') {
				result.append("&#037;");
			} else if (character == ';') {
				result.append("&#059;");
			} else if (character == '+') {
				result.append("&#043;");
			} else if (character == '-') {
				result.append("&#045;");
			} else {
				// the char is not a special one
				// add it to the result as is
				result.append(character);
			}
		}
		return result.toString();
	}
	
	//TODO do it more efficiently 
	public static String reconvertHTMLToChar(String str) {
		//all HTML escaped characters should start with "&" 
		if(!str.contains("&")) {
			return str;
		}
		str = str.replaceAll("&lt;", "<");
		str = str.replaceAll("&gt;", ">");
		str = str.replaceAll("&amp;", "&");
		str = str.replaceAll("&quot;", "\"");
		str = str.replaceAll("&#039;", "\'");
		str = str.replaceAll("&#040;", "(");
		str = str.replaceAll("&#041;", ")");
		str = str.replaceAll("&#035;", "#");
		str = str.replaceAll("&#037;", "%");
		str = str.replaceAll("&#059;", ";");
		str = str.replaceAll("&#043;", "+");
		str = str.replaceAll("&#045;", "-");
		return str;
	}
	
	public static native int getScreenWidth () /*-{
		return screen.width;
	}-*/;
	
	public static native String base64decode(final String data) /*-{

	var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
	var out = "", c1, c2, c3, e1, e2, e3, e4;
	for (var i = 0; i < data.length; ) {
		e1 = tab.indexOf(data.charAt(i++));
		e2 = tab.indexOf(data.charAt(i++));
		e3 = tab.indexOf(data.charAt(i++));
		e4 = tab.indexOf(data.charAt(i++));
		c1 = (e1 << 2) + (e2 >> 4);
		c2 = ((e2 & 15) << 4) + (e3 >> 2);
		c3 = ((e3 & 3) << 6) + e4;
		out += String.fromCharCode(c1);
		if (e3 != 64)
			out += String.fromCharCode(c2);
		if (e4 != 64)
			out += String.fromCharCode(c3);
	}
	return out;

	}-*/;
	
	
	public static native String base64encode(final String data) /*-{

	var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
	var out = "", c1, c2, c3, e1, e2, e3, e4;
    for (var i = 0; i < data.length; ) {
       c1 = data.charCodeAt(i++);
       c2 = data.charCodeAt(i++);
       c3 = data.charCodeAt(i++);
       e1 = c1 >> 2;
       e2 = ((c1 & 3) << 4) + (c2 >> 4);
       e3 = ((c2 & 15) << 2) + (c3 >> 6);
       e4 = c3 & 63;
       if (isNaN(c2))
         e3 = e4 = 64;
       else if (isNaN(c3))
         e4 = 64;
       out += tab.charAt(e1) + tab.charAt(e2) + tab.charAt(e3) + tab.charAt(e4);
    }
    return out;

	}-*/;
	

	public static native String md5(String string) /*-{
    	function RotateLeft(lValue, iShiftBits) {
    		return (lValue<<iShiftBits) | (lValue>>>(32-iShiftBits));
    	}

    	function AddUnsigned(lX,lY) {
		    var lX4,lY4,lX8,lY8,lResult;
		    lX8 = (lX & 0x80000000);
		    lY8 = (lY & 0x80000000);
		    lX4 = (lX & 0x40000000);
		    lY4 = (lY & 0x40000000);
		    lResult = (lX & 0x3FFFFFFF)+(lY & 0x3FFFFFFF);
		    if (lX4 & lY4) {
		    	return (lResult ^ 0x80000000 ^ lX8 ^ lY8);
		    }
		    if (lX4 | lY4) {
		    	if (lResult & 0x40000000) {
		    		return (lResult ^ 0xC0000000 ^ lX8 ^ lY8);
		    	} else {
		    		return (lResult ^ 0x40000000 ^ lX8 ^ lY8);
		    	}
		    } else {
		    	return (lResult ^ lX8 ^ lY8);
		    }
    	}

    	function F(x,y,z) { return (x & y) | ((~x) & z); }
    	function G(x,y,z) { return (x & z) | (y & (~z)); }
    	function H(x,y,z) { return (x ^ y ^ z); }
    	function I(x,y,z) { return (y ^ (x | (~z))); }

    	function FF(a,b,c,d,x,s,ac) {
    		a = AddUnsigned(a, AddUnsigned(AddUnsigned(F(b, c, d), x), ac));
    		return AddUnsigned(RotateLeft(a, s), b);
    	};

    	function GG(a,b,c,d,x,s,ac) {
    		a = AddUnsigned(a, AddUnsigned(AddUnsigned(G(b, c, d), x), ac));
    		return AddUnsigned(RotateLeft(a, s), b);
    	};

    	function HH(a,b,c,d,x,s,ac) {
    		a = AddUnsigned(a, AddUnsigned(AddUnsigned(H(b, c, d), x), ac));
    		return AddUnsigned(RotateLeft(a, s), b);
    	};

    	function II(a,b,c,d,x,s,ac) {
    		a = AddUnsigned(a, AddUnsigned(AddUnsigned(I(b, c, d), x), ac));
    		return AddUnsigned(RotateLeft(a, s), b);
    	};

    	function ConvertToWordArray(string) {
    		var lWordCount;
    		var lMessageLength = string.length;
    		var lNumberOfWords_temp1=lMessageLength + 8;
    		var lNumberOfWords_temp2=(lNumberOfWords_temp1-(lNumberOfWords_temp1 % 64))/64;
    		var lNumberOfWords = (lNumberOfWords_temp2+1)*16;
    		var lWordArray=Array(lNumberOfWords-1);
    		var lBytePosition = 0;
    		var lByteCount = 0;
    		while ( lByteCount < lMessageLength ) {
    			lWordCount = (lByteCount-(lByteCount % 4))/4;
    			lBytePosition = (lByteCount % 4)*8;
    			lWordArray[lWordCount] = (lWordArray[lWordCount] | (string.charCodeAt(lByteCount)<<lBytePosition));
    			lByteCount++;
    		}
		    lWordCount = (lByteCount-(lByteCount % 4))/4;
		    lBytePosition = (lByteCount % 4)*8;
		    lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80<<lBytePosition);
		    lWordArray[lNumberOfWords-2] = lMessageLength<<3;
		    lWordArray[lNumberOfWords-1] = lMessageLength>>>29;
		    return lWordArray;
    	};

    	function WordToHex(lValue) {
    		var WordToHexValue="",WordToHexValue_temp="",lByte,lCount;
    		for (lCount = 0;lCount<=3;lCount++) {
    			lByte = (lValue>>>(lCount*8)) & 255;
    			WordToHexValue_temp = "0" + lByte.toString(16);
    			WordToHexValue = WordToHexValue + WordToHexValue_temp.substr(WordToHexValue_temp.length-2,2);
    		}
    		return WordToHexValue;
    	};

	    function Utf8Encode(string) {
	    	string = string.replace(/\r\n/g,"\n");
	    	var utftext = "";
	
	    	for (var n = 0; n < string.length; n++) {
	
	    		var c = string.charCodeAt(n);
	
	    		if (c < 128) {
	    			utftext += String.fromCharCode(c);
	    		} else if ((c > 127) && (c < 2048)) {
	    			utftext += String.fromCharCode((c >> 6) | 192);
	    			utftext += String.fromCharCode((c & 63) | 128);
	    		} else {
	    			utftext += String.fromCharCode((c >> 12) | 224);
	    			utftext += String.fromCharCode(((c >> 6) & 63) | 128);
	    			utftext += String.fromCharCode((c & 63) | 128);
	    		}
	
	    	}
	
	    	return utftext;
	    };

	    var x=Array();
	    var k,AA,BB,CC,DD,a,b,c,d;
	    var S11=7, S12=12, S13=17, S14=22;
	    var S21=5, S22=9 , S23=14, S24=20;
	    var S31=4, S32=11, S33=16, S34=23;
	    var S41=6, S42=10, S43=15, S44=21;
	
	    string = Utf8Encode(string);

	    x = ConvertToWordArray(string);

    	a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476;

    	for (k=0;k<x.length;k+=16) {
    		AA=a; BB=b; CC=c; DD=d;
    		a=FF(a,b,c,d,x[k+0], S11,0xD76AA478);
		    d=FF(d,a,b,c,x[k+1], S12,0xE8C7B756);
		    c=FF(c,d,a,b,x[k+2], S13,0x242070DB);
		    b=FF(b,c,d,a,x[k+3], S14,0xC1BDCEEE);
		    a=FF(a,b,c,d,x[k+4], S11,0xF57C0FAF);
		    d=FF(d,a,b,c,x[k+5], S12,0x4787C62A);
		    c=FF(c,d,a,b,x[k+6], S13,0xA8304613);
		    b=FF(b,c,d,a,x[k+7], S14,0xFD469501);
		    a=FF(a,b,c,d,x[k+8], S11,0x698098D8);
		    d=FF(d,a,b,c,x[k+9], S12,0x8B44F7AF);
		    c=FF(c,d,a,b,x[k+10],S13,0xFFFF5BB1);
		    b=FF(b,c,d,a,x[k+11],S14,0x895CD7BE);
		    a=FF(a,b,c,d,x[k+12],S11,0x6B901122);
		    d=FF(d,a,b,c,x[k+13],S12,0xFD987193);
		    c=FF(c,d,a,b,x[k+14],S13,0xA679438E);
		    b=FF(b,c,d,a,x[k+15],S14,0x49B40821);
		    a=GG(a,b,c,d,x[k+1], S21,0xF61E2562);
		    d=GG(d,a,b,c,x[k+6], S22,0xC040B340);
		    c=GG(c,d,a,b,x[k+11],S23,0x265E5A51);
		    b=GG(b,c,d,a,x[k+0], S24,0xE9B6C7AA);
		    a=GG(a,b,c,d,x[k+5], S21,0xD62F105D);
		    d=GG(d,a,b,c,x[k+10],S22,0x2441453);
		    c=GG(c,d,a,b,x[k+15],S23,0xD8A1E681);
		    b=GG(b,c,d,a,x[k+4], S24,0xE7D3FBC8);
		    a=GG(a,b,c,d,x[k+9], S21,0x21E1CDE6);
		    d=GG(d,a,b,c,x[k+14],S22,0xC33707D6);
		    c=GG(c,d,a,b,x[k+3], S23,0xF4D50D87);
		    b=GG(b,c,d,a,x[k+8], S24,0x455A14ED);
		    a=GG(a,b,c,d,x[k+13],S21,0xA9E3E905);
		    d=GG(d,a,b,c,x[k+2], S22,0xFCEFA3F8);
		    c=GG(c,d,a,b,x[k+7], S23,0x676F02D9);
		    b=GG(b,c,d,a,x[k+12],S24,0x8D2A4C8A);
		    a=HH(a,b,c,d,x[k+5], S31,0xFFFA3942);
		    d=HH(d,a,b,c,x[k+8], S32,0x8771F681);
		    c=HH(c,d,a,b,x[k+11],S33,0x6D9D6122);
		    b=HH(b,c,d,a,x[k+14],S34,0xFDE5380C);
		    a=HH(a,b,c,d,x[k+1], S31,0xA4BEEA44);
		    d=HH(d,a,b,c,x[k+4], S32,0x4BDECFA9);
		    c=HH(c,d,a,b,x[k+7], S33,0xF6BB4B60);
		    b=HH(b,c,d,a,x[k+10],S34,0xBEBFBC70);
		    a=HH(a,b,c,d,x[k+13],S31,0x289B7EC6);
		    d=HH(d,a,b,c,x[k+0], S32,0xEAA127FA);
		    c=HH(c,d,a,b,x[k+3], S33,0xD4EF3085);
		    b=HH(b,c,d,a,x[k+6], S34,0x4881D05);
		    a=HH(a,b,c,d,x[k+9], S31,0xD9D4D039);
		    d=HH(d,a,b,c,x[k+12],S32,0xE6DB99E5);
		    c=HH(c,d,a,b,x[k+15],S33,0x1FA27CF8);
		    b=HH(b,c,d,a,x[k+2], S34,0xC4AC5665);
		    a=II(a,b,c,d,x[k+0], S41,0xF4292244);
		    d=II(d,a,b,c,x[k+7], S42,0x432AFF97);
		    c=II(c,d,a,b,x[k+14],S43,0xAB9423A7);
		    b=II(b,c,d,a,x[k+5], S44,0xFC93A039);
		    a=II(a,b,c,d,x[k+12],S41,0x655B59C3);
		    d=II(d,a,b,c,x[k+3], S42,0x8F0CCC92);
		    c=II(c,d,a,b,x[k+10],S43,0xFFEFF47D);
		    b=II(b,c,d,a,x[k+1], S44,0x85845DD1);
		    a=II(a,b,c,d,x[k+8], S41,0x6FA87E4F);
		    d=II(d,a,b,c,x[k+15],S42,0xFE2CE6E0);
		    c=II(c,d,a,b,x[k+6], S43,0xA3014314);
		    b=II(b,c,d,a,x[k+13],S44,0x4E0811A1);
		    a=II(a,b,c,d,x[k+4], S41,0xF7537E82);
		    d=II(d,a,b,c,x[k+11],S42,0xBD3AF235);
		    c=II(c,d,a,b,x[k+2], S43,0x2AD7D2BB);
		    b=II(b,c,d,a,x[k+9], S44,0xEB86D391);
		    a=AddUnsigned(a,AA);
		    b=AddUnsigned(b,BB);
		    c=AddUnsigned(c,CC);
		    d=AddUnsigned(d,DD);
    	}

    	var temp = WordToHex(a)+WordToHex(b)+WordToHex(c)+WordToHex(d);

    	return temp.toLowerCase();
    }-*/; 
}
